In the typical mining or quarrying operation, it is common practice to transport the overburden, mined material or stone to a crushing site where it is reduced in size. This requires a digging or blasting operation to first obtain the coarse material. It is then loaded onto trucks and transported to the crushing site. The transportation of the coarse material to the crushing site requires a large fleet of trucks as well as manpower to operate them.
One method of reducing hauling costs are mobile crushers. These are utilized to crush the coarse materials on site. The coarse materials are fed to the crushers by an excavating shovel. These materials are then moved from the crushing plant to the processing plant or an overburden pile by a conveyor.
In U.S. Pat. No. 4,486,049 there is described a mobile crusher with a hydraulic loader at its forward end. While the arrangement in this patent may obviate the need for a separate excavator or trucks to haul thematerials to the crusher, the digging mechanism is at the far outer end of the conveyor. Another disadvantage is the necessity to swivel the crusher and the need for an annular outlet conveyor.
The prior art does not provide a combined excavating and crushing apparatus for a continuous mining or quarrying operation wherein the dipper is of a large capacity and can be extended beyond the feeder conveyor as well as lowered around it so as to provide a large reach area for the machine. Neither does the prior art provide a continuous mining machine wherein a crusher is centrally mounted in the machine so as to provide a balancing weight for the unit yet avoid having to swivel the crusher.
It is an advantage of the present invention to provide an improved continous mining machine or the like which has a large reach area for the dipper.
It is another advantage of this invention to provide a continuous mining machine of the foregoing type wherein a gyratory crusher is centrally mounted in the machine for stability purposes.
It is yet another advantage of this invention to provide a continuous mining machine of the foregoing type which can be constructed from available time proven components thus reducing the cost of prototyping.
It is still another object of this invention to provide a continuous mining machine of the foregoing indicated type wherein the conveyors to and from the crusher unit are of a simplified nature.
Other features and advantages of the invention will become apparent as well as a better understanding of the invention from the descriptions following.